50 
A nima l Geography . 
[January, 
as the cockroach and the house-bug, are well known. If 
imported in articles of commerce they prove, as a rule, in- 
capable of maintaining themselves, and soon disappear. 
Like the Mammalia, their means of dispersal are mainly 
dependent upon “ the distribution of land and water, on the 
presence or absence of lofty mountains, desert plains, and 
great forests.” Strange as it may seem, we can also trace 
their existence and distribution in remote geological epochs, 
and can identify genera in the tertiary and families even in 
the palseozoic period. It is true that no part of the world 
would be so sharply demarcated by its entomological fauna 
as is Australia by its mammalian forms of life ; but this 
might not be wholly a disadvantage. Yet whilst we wish 
that an attempt might be made to draw up a system of 
animal geography based upon the distribution of inserts, we 
are strongly inclined to believe that the main results of such 
an undertaking would confirm the labours of Mr. Wallace. 
Even plants will doubtless be found to conform to the same 
arrangement. “ The florae of tropical America, of Australia, 
of South Africa, and of Indo-Malaya, stand out with as 
much individuality as the faunae, while the plants of the 
Palaeardtic and NearCtic regions exhibit resemblances and 
diversities of a character not unlike those found among the 
animals.” 
Before entering upon an examination of the system of 
Mr. Wallace we may find it useful to take a brief survey of 
the divisions proposed by earlier authorities. The first 
attempts in animal geography are due to Fabricius, the 
eminent entomologist. He divides the world into eight 
sections : the Indian, comprising the tropical regions of 
both hemispheres; the Egyptian, including the northern 
subtropical lands, apparently in the new as well as in the 
old continent ; the Mediterranean Islands, with southern 
Europe, and a part of Asia Minor; the North European; 
the North Asiatic ; the North American ; China, with Japan ; 
and, finally, all mountains throughout the globe which reach 
the level of perpetual snow. It does not appear that Fabri- 
cius ever made any attempt to demonstrate his theory, 
which must inevitably break down under even the most 
superficial analysis, and which merely serves to prove how 
little attention must have been paid in his day to the locali- 
ties of animal species. Latreille divides the world into 
“ climates,” each extending 12° of latitude by 24° of longi- 
tude. He does not, however, express himself satisfied that 
each of these plots is characterised by a distinct fauna. 
Kirby maintains that the limits of animal species are fixed 
